The present invention relates to a convection-enhanced delivery system for use in any targeted drug delivery procedure including convection-enhanced delivery (CED) and chronic intracranial administrations. CED is the continuous injection under positive pressure of a fluid containing a therapeutic agent. This technique is especially useful for administering therapeutic agents to tissues that are inaccessible via traditional oral medications or venous infusion techniques. For example, for central nervous system (CNS) applications, drug delivery by systemic or by intrathecal methods is not very effective because of the blood-brain bather and limitations with regard to the drug diffusion into the tissue. At best, traditional methods of treatment result in incomplete, non-targeted and heterogeneous dispersion throughout the CNS.
CED may be used to overcome some of the restrictions associated with traditional and other delivery systems. CED utilizes a pressure gradient to infuse substances directly into the interstitial space of a target tissue, for example a solid tumor tissue, via a catheter. This process is known as interstitial infusion and relies on bulk, convective flow and can be used to distribute both small and large molecular weight substances over clinically relevant volumes within solid tissue. Additional benefits include the ability to deliver the therapeutic at relatively constant concentrations throughout the volume of distribution.
The ability to accurately position the catheter within the target tissue is a difficult challenge requiring precise instrumentation and experienced hands. Once the catheter is accurately inserted to a desired depth, the position of the catheter must remain steady so as to ensure effective dispersion of the medicament within the target tissue. The catheter commonly remains inserted within the target tissue for weeks or months at a time to facilitate extended treatment times and the multiple treatment sessions required to achieve adequate tissue therapy. The patient must therefore be extremely cautious to prevent disruption of the catheter between, and during treatment sessions. Bandages, protective shells and the like are commonly used to assist the patient in maintaining the position of the catheter. However these methods are unsightly and inconvenient for the patient. Thus, while methods currently exist for maintaining the inserted position of CED catheters, challenges still exist. Accordingly, there is a need in the art for a delivery device system that is effective and convenient in assisting a patient in maintaining an inserted CED catheter without the drawbacks of currently available methods. Such a delivery device system is disclosed herein.